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Croaking Science: The benefits of green spaces and nature on mental health

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“In every walk with nature, one receives far more than he seeks” – John Muir

As well as the conservation work Froglife does for amphibians and reptiles across the UK, we also run projects that promote education amenities and research activities for the benefit of the public. We run wildlife projects for disadvantaged young people and those with dementia, such as our Green Pathways, Green Pathways for Life and Leaping forward for Dementia projects. A common issue amongst our participants is mental health, especially coming out the other side of the COVID-19 pandemic. Our Eco therapy style project is based on scientific research that suggests being outdoors and connecting with nature, have hugely positive effects on individuals.

As countries become increasingly urbanised, the world’s population is spending increasingly less time exposed to natural environments (Cox et al, 2018). It has been reported that 55% of the world’s population live in urban areas and this is expected to increase to 68% by 2050 (United Nations, 2018). Unfortunately, urbanisation not only means spending less time in natural environments but more time destroying them and reducing the number of green spaces around the globe (Collins, 2014). Aside from the detrimental environmental effects of this, loss of these green spaces and time spent in them could have hugely negative effects on people’s mental health and well-being.

There is growing evidence to suggest that being in nature has positive effects on people’s mental health. Studies have shown that green spaces can lower levels of stress (Wells et al, 2003) and reduce rates of depression and anxiety, reduce cortisol levels (Park et al, 2010) and improve general well-being. Not only can a simple walk in nature boost your mood but also improve your cognitive function and memory (Berman et al, 2012).  Green spaces can provide a buffer against the negative health impacts of stressful life events. A Dutch study showed that residents with a higher area of green spaces within a 3km radius had a better relationship with stressful life events (Van den Berg et al, 2010) which was soon to be increasingly important in recent years with the effects of COVID-19.

So what is it about natural environments that are good for mental health and wellbeing?

Positive Physiological effects

Something as simple as exposure to natural environments can be physiologically restorative (Conniff et al, 2014). This means that being in a natural outdoor environment can have positive mental health effects due to the physical processes elicited in the body. A Japanese study showed that viewing and walking in forest environments can promote lower concentrations of cortisol, lower pulse rates and blood pressure when compared to city environments (Park et al, 2010). These physiological effects are all a counter to the physical effects stress causes in the body and are what happens when you relax. A recent study found that those who had access to natural spaces during the COVID-19 lockdowns had lower levels of stress and those that could view nature from home had reduced psychological distress (Ribeiro et al, 2021).

There are multiple psychological theories as to how nature helps our mental well-being. The two common prevailing theories on how nature brings about these positive effects are the Stress Reduction Theory (SRT) coined by Ulrich (1981) and Kaplan et al’s (1989) Attention Restoration Theory (ART).  SRT suggests that nature promotes recovery from stress and that urban environments have the opposite effect. Ulrich proposes that being in unthreatening natural environments (a green space you would consider safe) activates a positive emotional response. That being in nature produces this as a universal innate connection, promoting the physiological effects of lower blood pressure, heart rate and increases attention which in turn blocks negative thoughts and emotions (Ulrich et al, 1991). Kaplan et al’s ART works around the idea that we have different types of attention: voluntary or involuntary, and that the latter requires no effort. After using voluntary attention we experience ‘attention fatigue’, reducing our cognitive abilities and increasing mental fatigue. According to Kaplan et al, when we use our involuntary attention it gives us time to restore our voluntary attention. From this, Kaplan et al have suggested that what nature provides acts as a restorative power by providing four processes:

  • Being away – an opportunity to distance from routine activities and thoughts.
  • Soft fascination – nature holds attention effortlessly: think about the sunsets, sound of water, leaves blowing in the wind all-natural phenomena allowing your voluntary attention to rest.
  • Extent – nature provides an immersion experience, engaging the mind and rest from concerns.
  • Compatibility – a setting that is well matched to human needs and desires, providing a feeling of being in harmony with a greater whole.

These two theories have much in common: they focus on cognitive vs autonomic processes and both support a change in attention and stress load when an individual interacts with the natural environment (Gregory N. Bratman, 2012). However, they differ in how they suggest the primary mechanisms work. The effects the theories suggest are blurred in the sense of cause and effect: does a reduction in stress levels allow someone to concentrate better or does replenished direct attention help reduce stress?

Both these assertions are controversial in the field of environmental psychology, yet much research falls under either both or one of these theories.

Mental Health and Nature Policy

To what degree these theories influence policy is debated but it is clear that in recent years, especially after the recent pandemic, that nature spaces are becoming an increasing priority for mental health provision. Research has evidenced that we need to shift our attention from focusing on people visiting green spaces to how we interact and connect with nature close to home through simple activities (Mental Health Foundation, 2021). The Mental Health Foundation suggests from their research findings that we need to focus on six main areas in policy:

  1. Facilitating connection with nature
  2. Protecting the natural environment and restoring biodiversity
  3. Improving access to nature
  4. Making green spaces safe for all
  5. Using the planning system and urban design to improve the visibility of nature in every local area
  6. Developing a life – long relationship with nature.

Through our projects at Froglife we provide ways for people to interact with the environment instead of simply just being in it.

Promotion of Physical activity

Green spaces such as nature reserves, wilderness environments and urban parks also promote certain behaviours, such as encouraging physical activity within the space, which is a pro-mental health behaviour. Experimental studies have shown that not only do green spaces promote experience but they may be better for mental health than activity in other environments. Those that perform exercise in natural environments once a week are at about half the risk of poor mental health as those that don’t (Mitchell, 2013). Participation and involvement in nature is often tied to physical activities such as gardening or farming, trekking or running: the evidence of the benefits of this promotes the idea that green spaces should be seen as an essential health resource (Pretty, 2004).

There are many more benefits associated with natural green spaces. However, in terms of mental well-being, greener areas have been associated with a sustained improvement in mental health, highlighting the significance of green spaces, especially in urban areas. They provide not only a habitat for wildlife but also sustainable public health benefits (Alcock et al, 2014). Many studies have shown that more time spent in nature is associated with better mental health, independent of culture and climatic contexts, as well as the promotion of physical activity.

In addition to the wildlife and environmental benefits of conserving nature spaces, especially in urban areas, we also benefit in many ways from these natural spaces. This gives us even more reason to continue to protect our wildlife and conserve our natural areas and green space.

 

References

Alcock, I, et al., 2014. Longitudinal Effects on Mental Health of Moving to Greener and Less Green Urban Areas. Environmental Science & Technology , 48, 1247-1255.

Berman, M.G, et al., 2012. Interacting with nature improves cognition and affect for individuals with depression. Journal of Affective Disorders, 140, 300-305.

Bratman, M.G, et al., 2012. The impacts of nature experience on human cognitive function and mental health. Annals of the New York Academy of Sciences (Issue: The Year in Ecology and Conservation Biology), 1249, 118-136.

Collins, A.M., 2014. Destruction of urban green spaces: A problem beyond urbanization in Kumasi city (Ghana). American Joural of Environmental Protection, 3, 1-9.

Conniff, A, et al., 2016. A methodological approach to understanding the wellbeing and restorative benefits associated with greenspace. Urban Forestry & Urban Greening, 19, 103-109

Cox, D.T.C, et al., 2018. The impact of urbanisation on nature dose and the implications for human health. Landscape and Urban Planning, 179, 72-82.

Kaplan, R, et al., 1989. The Experience of Nature: A Psychological Perspective. New York: Cambridge University Press.

Mental Health Foundation, 2021. Nature- How Connecting with nature benefits our mental health. Published on-line.

Mitchell, R., 2013. Is physical activity in natural environments better for mental health than physical activity in other environments? Social Science & Medicine, 91, 130-134.

Park, B.J, et al., 2010. The physiological effects of Shinrin-yoku (taking in the forest atmosphere or forest bathing): evidence from field experiments in 24 forests across Japan. Environmental Health and Preventative Medicine, 15, 18-26.

Pretty, P. J., 2004. How nature contributes to mental and physical health. Spirituality and Health International, 5, 68-78.

Ribeiro, A.I, et al., 2021. Exposure to nature and mental health outcomes during COVID-19 lockdown. A comparison between Portugal and Spain. Environment International, 154 article 106664.

Ulrich, R. S., 1981. Natural Versus Urban Scenes: Some Psychophysiological Effects. Environment and Behavior 13, 523-556.

Ulrich, R. S., et al., 1991. Stress recovery during exposure to natural and urban environments. Journal of Environmental Psychology, 11, 201-230.

Van den Berg, A. E, et al., 2010. Green space as a buffer between stressful life events and health. Social Science & Medicine, 70, 1203-1210.

Wells, N.M. & Evans, G.W., 2003. Nearby Nature: A Buffer of Life Stress among Rural Children. Environment and Behavior, 35, 311-330.

Parental care in amphibians: research findings from 1705 to the present day

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Writen by Roger Downie, University of Glasgow and Froglife

Croaking Science does not usually urge its readers to study a particular scientific paper, but this is an exception. The paper is Schulte et al.’s (2020) review of research into amphibian parental care, a fascinating and essential read for all amphibian enthusiasts. Parental care is usually defined as ‘non-gametic investments in offspring that incur a cost to the parent’ and which provide some benefit to the offspring. Common examples are egg-guarding, and provisioning of young after hatching. Although some authors restrict discussions of parental care to actions that occur after fertilisation, others include activities like nest-building in preparation for egg laying. For example, we generally consider UK amphibians as lacking parental care: they deposit their eggs in water, then leave. But Schulte et al include the behaviour of female newts that wrap their eggs individually in leaves: this behaviour takes a substantial amount of time, so is costly to the female, and contributes to offspring survival by reducing predation.

Research into parental care tends to focus disproportionately on birds and mammals. Stahlschmidt (2011) in a review of what he termed ‘taxonomic chauvinisn’ found amphibian and reptile parental care much less studied than cases from birds, mammals and even fish. Schulte at al. redress this situation through a vast historically-based review, identifying 685 studies spanning the period 1705-2017. Early studies were mainly simply descriptive, but since 1950, there has been a greater focus on the investigation of explanations: what does parental care achieve, and what does it cost?

The paper’s Table 1 lists each of the parental care modes so far described: four in Caecilians; eight in Urodeles; 28 in Anurans. Some modes occur in all three Orders e.g. terrestrial egg guarding; others occur in only one Order e.g. wrapping of individual eggs in leaves by newts; foam-nest construction by many frogs. Overall, parental care is known from 56 (74%) of the amphibian Families. It is not really surprising that more parental care modes occur in the Anurans than in the other two Orders, since anuran species diversity is so high (Frost, 2021 lists 7406 anurans, 768 urodeles and 212 caecilians).

The first known report of parental care in an amphibian, remarkably, was by a German female natural historian and artist, Maria Sibylla Merian in 1705. Her book was mainly devoted to meticulous drawings of the insects she observed in Suriname, but she also included an illustration and observations on an aquatic frog, later named the Suriname toad (Pipa pipa), which incubates its eggs in individual pockets on its back: she saw the metamorphosed juveniles emerging from the pockets. I was lucky, on my first visit to Trinidad, to see this for myself. We captured a ‘pregnant’ female and the babies later hatched into the water, some still with tail stumps, others fully metamorphosed. Female biologists have been prominent in the study of amphibian parental care: in addition to Maria Sibylla Merian, Martha Crump (1996) and Bertha Lutz (1947) come to mind, as well as the four authors of the review under discussion.

Suriname Toad

Among the 500 or so papers that Schulte et al. cite, I was pleased to see two from the work we have done in Trinidad (Downie et al., 2001; Downie et al., 2005). These are about the Trinidad stream frog Mannophryne trinitatis (see Croaking Science September 2020), where the fathers guard the eggs on land then transport hatchlings on their backs to a pool where they can complete development to metamorphosis. Tadpole transportation is a common aspect of parental care in the neotropical families Dendrobatidae and Aromobatidae. We found that the fathers are choosy over where to deposit their tadpoles, avoiding pools that contain potential predators, and therefore contributing to their survival. The search could take up to four days. We wondered how costly this might be to fathers: to our surprise, transporting a relatively heavy load of tadpoles did not appear to reduce the fathers’ jumping ability, nor did it prevent them from finding food. However, four days away from their territory must count as at least some cost in terms of lost mating opportunities.

A male Trinidad stream frog, Mannophryne trinitatis transporting his tadpoles (photo credit: Joanna Smith)

Schulte et al. conclude with a timely plea for a revival of teaching and research in natural history. As they say, natural history observations – on the distribution, numbers and habits of organisms- form the basis of all new ideas and hypotheses in ecology and evolutionary biology. They note that there remain many amphibian species whose habits are poorly known and that many novel observations have been made on parental care in recent years. They therefore expect that much could be discovered, as long as effort is put into new field work. Over 20 years ago, I wrote lamenting the modern status of natural history (Downie 1997, 1999), and Schulte et al. report that the loss of organism-based teaching and research is widespread. In the UK, there are moves to create a natural history curriculum, to complement biology in schools. I feel that it is much needed.

References

Crump (1996). Parental care among the amphibia. Advances in the Study of Behaviour 25, 109-144.

Downie (1997). Are the naturalists dying off? The Glasgow Naturalist 23 (2), 1.

Downie (1999). What is natural history, and what is its role? The Glasgow Naturalist 23 (4), 1.

Downie et al. (2001). Selection of tadpole deposition sites by male Trinidadian stream frogs (Mannophryne trinitatis; Dendrobatidae): an example of anti-predator behaviour. Herpetological Journal 11, 91-100.

Downie et al. (2005). Are there costs to extended larval transport in the Trinidadian stream frog (Mannophryne trinitatis, Dendrobatidae)? Journal of Natural History 39, 2023-2034.

Frost (2021). Amphibian species of the world : an online reference. Version 6.1 (accessed 29/9/21). Electronic database accessible at http://amphibiansoftheworld.amnh.org/index.php. American Museum of Natural History, New York, USA.

Lutz (1947). Trends towards non-aquatic and direct development in frogs. Copeia 1947, 242-252.

Schulte et al. (2020). Developments in amphibian parental care research: history, present advances, and future perspectives. Herpetological Monographs 34, 71-97.

Stahlschmidt (2011). Taxonomic chauvinism revisited: insight from parental care research. PLoS ONE 6, e24192.

Halloween, Folklore and Myths

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“Fillet of a fenny snake, In the cauldron boil and bake; Eye of newt and toe of frog, Wool of bat and tongue of dog, Adder’s fork and blind-worm’s sting, Lizard’s leg and owlet’s wing, For a charm of powerful trouble, Like a hell-broth boil and bubble.”

For many, the above passage will be familiar as a scene from Shakespeare’s Macbeth.  For those who are not familiar, most will at least know that it is in reference to a witch’s brew. Amphibians and reptiles have long been associated with the occult, having deep rooted ties to ancient folklore and mythology. Though these links are not as strong in the present, the negative stigma surrounding these species has pervaded. What better time than Halloween to delve into these stories and perform some much-needed myth busting?

Did witches really go around carving out newt eyes, leaving blind newts to stumble around lost? The answer is no. In Shakespeare’s Elizabethan England, jobs such as midwives, herbalists and healers were easily misunderstood, and deemed witchcraft as a result. In an age predating modern medicine, people had to be more connected with nature to create medicines. They had to understand what was usable and what was not, which combinations worked for which illnesses etcetera. This makes complete sense, as we today still rely on nature for the base ingredients of many of our own medicines. These tradespeople relied on knowledge passed down through generations to create herbal remedies. To protect their livelihoods, their ingredients had to be shrouded in secrecy. This is no different to giant companies today like Coca Cola hiding the ingredients to their “magical brews”.

In order to keep their ingredients secret, they renamed a lot of what they used. This would also deter others from taking up the same practices; as animal body parts hardly sounds appealing and there’s no business in having everyone trained as a healer! If we look at Shakespeare’s cauldron, what was really being used was mustard seeds (eye of newt), buttercup (toe of frog), holly leaves (wool of bat) and houndstongue (tongue of dog). The use of body parts to refer to parts of plants was common within these circles. Eyes would refer to seeds, tongues to petals, guts to roots, tail to stem and so forth. Admittedly, adder’s fork did refer to an adder’s tongue and a blind worm’s sting referred to a slow worm’s tail. That aside, selling potions with mysterious names would prevent customers from simply going off and making their own potions. The witchy aura of it all also may have legitimised the healer and had consumers convinced that they were taking magical cures – not too different to the placebo effect we know of today.

Still, this does not answer the question of why there is such a gravitation towards reptiles and amphibians. Why do they inspire such revulsion? From medieval times, it was believed that all toads and frogs were poisonous. This is the case for some species, but certainly not within the UK. The fear stemmed from the fact that some amphibians can cause sickness or fatality if ingested – in particular, toads, as they release bufotoxin to deter predators when frightened. Furthermore, during breeding season, it is known that these animals can swarm in large numbers. In times past, animals swarming was not seen as a marvel of nature, but instead a precursor of evil. Think of a swarm of locusts for example. They can be found in such quantities that people feared that they were spontaneously multiplying. Their choice of habitat invoked further fear as swamps and stagnant pools of water were the antithesis of consecrated holy water. The list goes on.

However, it did not always use to be that way. Frogs used to symbolise fortune, rebirth, rain, fertility and heightened spirituality. The Egyptian goddess Heqet, occasionally depicted with a frog’s head, was the goddess of fertility and childbirth. Rain was a giver of life, allowing crops to grow and rivers to flow and consequently frogs became predictors of rain as they would gather in large numbers as the heavens showered. This was a trait that was also shared with other amphibians such as our toads and newts. Snakes symbolised immortality with their skin shedding, lizards represented regeneration due to their ability to regrow tails. As we celebrate Halloween, it is perhaps a time to reflect and rediscover the awe of the Ancient Egyptians and Mesopotamians. Rather than perceive the brilliant nature of metamorphosis as these species morph from egg to adult as something to fear, it is time to shift back to the perspective that it is a magic to be revered and protected at all costs.

Emily Robinson, London T.O.A.D Project Trainee

Croaking Science: Amphibians in the ‘Anthropause’

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On damp nights in the spring in temperate regions, amphibians emerge from their winter hideouts to migrate to their breeding pools. Nothing will stop their drive to reach water to spawn and so they brave a barrage of cars and artificial barriers along their route which often results in them getting squashed.

Amphibians have complex, biphasic life histories which makes their conservation challenging. Most species require high quality aquatic and terrestrial habitats which must both be connected by a transition habitat during migrations (Baldwin et al. 2006). 

As urbanisation expands around the world, many aspects of wildlife physiology, movement patterns, population genetics and overall health are affected due to anthropogenic stressors such as habitat loss and artificial light pollution. The unprecedented expansion in transport infrastructure in the past century has had massive impacts on amphibian populations around the world (Beebee 2013, Glista et al. 2008). Roads fragment habitats and cause high mortality as well as being a significant source of chemical contaminants (Petrovan and Schmidt 2016, White et al. 2017, Bird et al. 2019). 

Roads which bisect migratory routes severely restrict the dispersal of amphibians between their breeding areas and terrestrial habitat. This can have catastrophic impacts on gene flow and metapopulation dynamics potentially leading to population declines, genetic isolation and even extinction (Fahrig and Rytwinski 2009, Marsh and Trenham 2001). Therefore, mitigating road-kill and habitat fragmentation is a conservation priority (Puky 2005, Beebee 2013, Cushman 2005). Genetic bottlenecks as a result of fragmentation reduce the viability of populations and can leave amphibians more vulnerable to other synergistic environmental stressors such as climate change, pollution and emerging wildlife diseases (Cushman 2005, Laurence and Useche 2009). Urban fragmentation is known to decrease species diversity and abundance and coupled with wider habitat degradation such as edge effects and loss of breeding habitats, can make cities particularly challenging for amphibians (Bickford et al. 2011, Scheffers and Paszkowski 2012). At some field sites, mass mortality on roads can cause complete extirpation of anurans and salamanders within years (Cooke 2011, Hels and Buchwald 2000). With more and more cars on the roads, it is increasingly difficult for amphibians to avoid them. 

Common toads

Temperate amphibians such as the common toad have experienced significant and continuous declines. In the UK it is estimated that 20 tonnes of common toads (Bufo bufo) are killed annually as they migrate across roads to reach their breeding ponds, with up to 13,000 annual mortalities being recorded even at manned amphibian crossings. This has contributed to a 68% decline in their population size in the past 50 years at a rate of 2.26% per year. The severity of the population reduction means that these toads are no longer ‘common’ toads and could soon qualify as vulnerable on the IUCN Red List (Petrovan and Schmidt 2016).

The COVID-19 pandemic has caused immense human tragedy as it has spread around the world straining healthcare services and paralysing economic systems. Quarantine restrictions imposed by governments in order to slow the spread of the virus, have caused extraordinary disruption to our globalised society but have created rare opportunities for some wildlife species (Zellmer et al. 2020). As bustling metropolises slowed down they were occupied by usually elusive fauna; wild boars were seen roaming Barcelona’s quiet neighbourhoods, flamingos flocked to New Delhi’s lakes, river otters and puma stalked silent streets in Chile and sea turtles thrived on empty Brazilian beaches. A recent paper by Rutz et al. (2020) coined the term ‘anthropause’ for this rapid and unprecedented “global slowing down of modern human activities, notably travel.” It has resulted in profound short term environmental benefits such as improved air and water quality as well as reduced wildlife disturbance. 

Research conducted during the Anthropause has highlighted both known and less known impacts that we are having on the natural world and is providing a unique opportunity to study wildlife populations during a time of reduced human presence all around the world (Forti et al. 2020, Zellmer et al. 2020, Bates et al. 2020). Monitoring the ways wildlife has responded to covid lockdowns in urban areas allows researchers to quantify the impacts human mobility is having on wildlife in the Anthropocene (the term given to our geological age, dominated by human activities) and potentially find strategies to mitigate biodiversity loss (Rutz et al. 2020, Stokstad 2020). This research provides invaluable insight into the mechanisms of human-wildlife interactions that will inform conservation for decades to come. 

Lockdowns in spring and summer of 2020 meant fewer vehicles on the road which has significantly decreased road mortality for many species including amphibians. A “roadkill reprieve” this year may have made amphibian migratory journeys much safer according to Goldfarb (2020).  A study by Grilo et al. (2020) calculated that 194 million birds and 29 million mammals are killed on European roads each year under normal circumstances while in Brazil, road mortality has superseded hunting to become the “leading cause of direct human caused mortality in terrestrial vertebrates” (Carvalho et al. 2014). This year they may not suffer the same fate. Simply driving less could have been “the biggest conservation action” taken by humanity over the past 50 years according to Fraser Shilling of the Road Ecology Centre at UC Davis and could have potentially saved the lives of 500 million vertebrates (Nguyen et al. 2020). 

In March and April as traffic flows dipped by 73% across the US, many creatures received temporary respite from road collisions, with Californian mountain lion fatalities down 58% and a 48% decrease in roadkill deaths in Maine. Although much of the data focuses on large mammals, the same is true for smaller, less mobile animals such as amphibians, snakes and turtles (Katz 2020). 

At amphibian crossings this spring in Maine, wood frogs, salamanders and newts were twice as likely to survive than in previous years, which is great news for these sensitive creatures that are very vulnerable to habitat fragmentation.  Four amphibians successfully crossed the road for every one squashed this year, half as many as in previous years (Goldfarb 2020, Keim 2020).

Wood frog (Photo Credit: Brian Gratwicke)

A study by Manenti et al. (2020) examined the effects of the COVID-19 lockdown and reduced human disturbance on wildlife in Italy and describes both positive and negative effects on biodiversity conservation. As well as allowing wildlife to explore new habitats and extend their activity periods, species richness and reproductive success increased while roadkill diminished in temporarily quieter areas. Some negative ecological effects included reduced enforcement of regulations, and postponed conservation action such as invasive species management. 

A decrease in road traffic led to significantly improved survival of migrating amphibians on Italian roads this spring at eight toad crossings. Data suggests that there was an 80-90% decrease in nocturnal road traffic at these study sites during the anthropause. Four hundred and eight common toads (Bufo bufo) and 16 agile frogs (Rana dalmatina) were recorded as roadkill in 2019, and this dropped to only 38 toads and zero agile frog mortalities in 2020. The median mortality of road killed amphibians at each site decreased from 53 individuals to only one in 2020 (with some sites recording no mortalities) indicating that an increased number of adults made it to their breeding pools this spring giving populations a much needed boost. Manenti et al. (2020) also surveyed transects in Liguria, Northern Italy to quantify the effects of reduced traffic on common wall lizards (Podarcis muralis) and Western green lizards (Lacerta bilineata) and found a similar 10-fold decrease in road mortality. 

Many of the conservation benefits the Anthropause created are ephemeral, as traffic returned to baseline levels once economic activity restarted. Although breeding booms this spring may bring some respite to struggling populations, alone, they will not be able to counteract the extreme loss of genetic diversity as a result of population bottlenecks in the past. 

The information collected over the Anthropause highlights the need to improve the landscape to make it safer for all wildlife and particularly amphibians (Merrow 2007). If we can alter our transport networks to counter the effects of large-scale urban development and increased transport infrastructure we could go some way to mitigating the catastrophic impact of habitat fragmentation. The observed benefits that limiting road traffic can provide for migrating amphibians could inform more decisions about temporary, focused road closures around the world in the future to replicate this effect and to better conserve endangered amphibian and reptile species (Manteni et al. 2020).

Building fauna tunnels and bridges across dangerous roads to link habitat fragments allows animals to cross safely (Dodd et al. 2004, Gonzalez-Gallina 2018, Vartan 2017). Road mortality decreases by up to 85%-95% with animals responding surprisingly quickly to the change as ecosystems are reconnected (Vartan 2019). Wildlife tunnel projects can mitigate the effects of fragmentation and have been shown to allow amphibians to move successfully between sites bisected by roads. Tunnels and drift fences reduce road mortality, promote habitat connectivity, and allow amphibians to colonise new ponds leading to population increases and expansion into reconnected habitat (Jarvis et al. 2019). These movement corridors also allow roads to be permeable to a host of other wildlife species like reptiles and small mammals (Purky 2005, Jarvis et al. 2019). 

The incredible work done by volunteers at amphibian crossings who help migrating amphibians make it across roads (Petrovan and Schmidt 2016) could also contribute to sustaining population increases this spring from quieter road traffic. 

COVID-19 has also highlighted how explicitly intertwined human and wildlife health are and the catastrophic impacts of the overexploitation of nature. Emerging wildlife diseases such as chytrid fungi and ranaviruses threaten amphibians around the world and their spread has been catalysed by anthropogenic trade in our globalised world (O’Hanlon et al. 2019). A slowdown in global trade and human flows as a result of COVID-19 could also have gone a way to mitigating the spread of the pathogens that imperil amphibians (Forti et al. 2020). Although this benefit may only be short-lived as economies restart, there is hope that better regulation of the wildlife trade, in order to decrease the chances that future novel zoonotic diseases spill over from wildlife reservoirs in the future, could benefit amphibians too. Since the wildlife trade is responsible for the translocation of many amphibian pathogens (Kolby et al. 2014, O’Hanlon et al. 2018) better regulation and enforcement of the trade in live animals could help stem the spread of emerging amphibian diseases and invasive species (Forti et al. 2020). 

The Anthropause provides us with an excellent opportunity to reimagine our relationship with nature and our socio-economic systems so that biodiversity can flourish and acts as a reminder that biodiversity is essential for maintaining human health and wellbeing too.

The disruption to the economic status quo that the pandemic has created gives us a pivotal opportunity to consider a greener, more sustainable future where people and wildlife can thrive. In order to effectively stem biodiversity loss in the Anthropocene, we must use this pivotal moment to plan a green recovery which incorporates wildlife conservation into all economic rebound projects. In the UK this means not viewing the protection of  great crested newts as a delay to construction (Howard 2020) but valuing them as integral parts of a plan to balance our economic and environmental ambitions. It is also a perfect opportunity to invest in road mitigation measures such as wildlife tunnels and fauna bridges to reduce the detrimental impact they can have on wildlife populations (Merrow 2007), with the added benefit of being excellent economic multipliers.

November 2020 Croaking Science article by Xavier Mahele 

Bibliography

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Goldfarb B (2020). Lockdowns Could Be the ‘Biggest Conservation Action’ in a Century. The Atlantic.

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What our animals are doing this month… November 2020

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We’ve recently covered what our amphibians and reptiles are up to over the autumn months, the differences in their overwintering behaviour and where they may spend the colder seasons in structures such as hibernacula. 

It might surprise many however to hear that November can be a month for sighting Common Frogspawn in the south of England.  Common frogs usually begin breeding and laying spawn as spring commences – often with sightings in January and February into spring depending on their location in the UK.  But areas in Cornwall do report sightings of frogspawn before winter even fully commences.

This behaviour could be due to confusion during mild autumn and winter months that we can experience now in the UK or might be a strategy to get ahead of the game in terms of breeding times – albeit it with a huge risk of freezing temperatures affecting the survivability of the spawn.

This could be one sign of more to come in terms of our amphibians adapting to the effects of climate change and seasonal differences their behaviour isn’t quite adapted to.  It’s so important that we can monitor these yearly trends in our amphibian and reptile species to help inform our work at Froglife and you can help by submitting your sightings using the Dragon Finder App – available for free on Android and iPhone devices!

Frogspawn in November? Surely not! But this sighting can occur in mild autumns in the south of England

What our animals are doing this month… October 2020

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October is truly a season of change for our native flora and fauna. As the temperature drops, vegetation starts to die back and our days get shorter, our native amphibians and reptiles start to get ready to face the challenge of winter. 

Why is winter so challenging for our native Dragons?! Amphibians and reptiles are both ectotherms, meaning that they rely on external sources of body heat compared to endotherms, such as mammals, which are capable and dependent on internal generation of heat. This means that amphibians and reptiles have to find a way to navigate through the drop in external temperature, frozen watery homes, reduction in water oxygen levels and, often unforgiving, winter weather.

Each species has clever adaptions and behavioural changes that they go through each year between September and November for them to survive this wintery challenge.

It is a common misconsception that all amphibians and reptiles hibernate over winter, even though they will all be seeking hibernacula at a similar time, the type they need can differ from species to species as well as if they hibernate or overwinter.  For example, the common lizard will be spending October feeding on invertebrates in preparation for winter before hibernating, often in groups, amongst rocks or dead wood.

Common Lizard

Whereas, our newt species overwinter and go dormant under rocks or buried in mud, but take advantage of milder weather to forage.

Palmate Newt

For more info on what individual species do over winter have a look at our fatastic amphibian and reptile fact files! Click here!

By early October most of our reptile species will have entered their winter hibernation. The majority of the UKs reptile species will have favoured hibernating sites, such as the Adder who will return to their wintering sites that they use each year. With Adders often basking in the last of the autumnal sunshine until the end of October when they become dormant for the colder months.

Adder

Some species, particularly slow-worms, common lizards and grass snakes, will make use of piles of dead logs, leaves or compost for the winter. It is important that reptiles are not disturbed during their hibernation period since it takes them longer to recover if they have to become active.

An amazing way to help our fantastic amphibians and reptiles is to consider them when planning your wildlife garden. One of my favourite things to do is create a hibernaculum, an amazing space for all amphibians and reptiles to hunt, forage and of course over winter. They are so simple to do and can make such a difference! If you are short on space you could also make a ‘toad home’!

Would you like to create more overwintering ad hibernating homes for wildlife? Create new habitats for emerging amphibians and reptiles in Spring?

Download our FREE Wildlife Pond Visualizer App, learn what you can do for nature and try out the fantastic Augmented Reality Feature!

For more information click here. Download here

We would love to see pictures of all your hard work! Send in your before and after photos or gardening selifes to info@froglife.org

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